Freshwater Shrimp Cocktail

Daniel Linton

One of the most exciting aspects of the aquarium hobby is when a new breakthrough happens. Such a breakthrough might consist of a new product, new technology, a new color variation or possibly the most exciting: the discovery of a new species. Very rarely does the type of breakthrough occur when a whole new category of the aquarium hobby is born. When I use the term category, I mean a whole broad segment such as: cichlids, livebearers, killifish, or planted aquaria. Over the past few years, aquarists have witnessed and participated in the birth of a brand new category: freshwater invertebrates. Since 2003, freshwater invertebrates have become one of the fastest growing areas of the American aquarium hobby. This growth is due to an influx of new species, new knowledge and a huge spike in invertebrate interest. Many different creatures are grouped under the heading freshwater inverts, including: shrimp, crabs, crayfish and aquatic insects. This article will eschew the broad categorization and focus on dwarf algae eating shrimp.

Dwarf algae eating shrimp were first introduced to aquarists worldwide by famed aquascaper Takashi Amano. Amano featured Japonica/Amano shrimp Caridina japonica, in his Nature World Aquarium Vol. 1(1994). The Japonica shrimp were used to control algae and provide biodiversity in Amano’s aquascaped creations. Japonica/ Amano shrimp became the first widely available algae eating shrimp in the United States. Japonica shrimp because of their durability, availability, and size usually serve as most aquarists first experience keeping algae eating shrimp. Amano shrimp because of their size can be housed with peaceful small fish.

If there were one thing that I hope for this article to accomplish, which would be to make the reader aware of how much fish like to eat and harass shrimp. Most of the smaller shrimp species are easily eaten by even the smallest species of fish. Amano shrimp and other large species can be housed with small peaceful fish however small species such as Cherry shrimp Neocaridinaheterpoda should be housed alone. If one really wanted to house fish with small shrimp I would recommend tiny,small-mouthed fishes such as Heterandriaformosaor PseudomugilRainbow species. I have seen shrimp killed and eaten by tiny fish ranging from licorice gouramis(Parosphromenusdeissneri)toEndler’s livebearers.

Dwarf shrimp can be kept with non-predatory catfish such as Corydoras catfish and small suckermouth catfishes such as Ancistrussp. I have found that shrimp love to sift through and feed on catfish excrement. Shrimp however may be injured or killed when catfish “ freak out” and race around the aquarium. From my experience shrimp tend to be more timid and hide more when housed with fish. For one to attain the most rewarding shrimp keeping experience, I would recommend maintaining a “shrimp only” aquarium.

Dwarf algae eating shrimp rarely grow over 2 inches in length; Amano shrimp are the species that grow the largest. The majority of algae eating shrimp including Cherry shrimp and Crystal Red shrimpCaridinacantonensis sp. Crystal Red, will not exceed much more than one inch in length. Algae eating shrimp species become sexually mature at around five or six months of age. Most dwarf algae eating shrimp have a lifespan of about eighteen months. Amano shrimp C. japonica have been rumored to live five or as long as ten years. The tiny Hawaiian Red shrimp Halocaridinarubra may live for twenty years ( Ucolzler, 2008).

Algae eating shrimp live in dense colonies, when displayed in a shrimp only aquarium, a colony may have the appearance of an aquatic ant farm. Many interesting behaviors can be witnessed when a colony is observed. Algae eating shrimp do not eat their young so many generations can be housed together. Brightly colored females who are holding eggs in their swimmerets are referred to as being “berried”. The clusters of brightly colored round eggs resemble clusters of berries. Females of most dwarf species carry eggs for between 21 and 28 days.

Male shrimp in many species are usually less colorful than females. Males also have smaller less full bodies than females and shorter swimmerets. Mating can sometimes be observed when a male mounts a female. The ovaries of a “ripe” female shrimp can be observed on their dorsal area. The ovary area is called the saddle because it resembles a small English riding saddle on the back of the shrimp.

Algae eating shrimp species are ideal residents for planted nano aquariums. Even a small colony of shrimp can be kept in a two and a half gallon aquarium. A more suitable aquarium for shrimp would be at least ten gallons. Heating may not even be needed for a shrimp aquarium if you house the aquarium in a warm location. Many species of algae eating shrimp can survive temperatures that dip into the fifties. Most species need a sustained temperature of 68+ degrees for reproduction to occur. Shrimp do not do well at very high temperatures and may begin to perish when temperatures begin to exceed ninety degrees. The majority of dwarf algae eating shrimp species thrive in conditions that are fairly cool at around 72 degrees. Many shrimp are not as colorful at high temperatures. The white area on Crystal Red shrimp is not as bright in very warm water.

Lighting is an important factor when setting up a shrimp aquarium. Providing enough light is crucial for the plant life and the algae, upon which the shrimp feed to flourish. I have experimented using power compact lights on shrimp aquariums and have had excellent results. The power compact lights definitely benefit the plant and algae growth. The shrimp also seemed more vigorous and reproduced at a higher rate than under fluorescent lighting. Perhaps the shrimp were able to glean extra vitamins and benefitted from the more powerful lighting spectrum. Natural sunlight can prove very beneficial for the shrimp aquarium. In aquariums that received natural sunlight I have observed some of the most colorful shrimp and highest reproduction rates that I have encountered since I began shrimp keeping.

Several safety issues should be considered when choosing the filtration for a shrimp aquarium. First select a filter that will not suck adult or young shrimp inside. Second shrimp do not like a strong current so a filter with a flow that can be turned down is necessary. When using a power filter or canister filter the intake should be covered so shrimp are not sucked inside. A commercially available prefilter sponge can be purchased. As an alternative a homemade cover can be made from a block of aquarium safe foam with a slit cut into it can be slipped over the filter intake.

The mode of filtration that I prefer to use for a shrimp aquarium is a sponge filter. A sponge is usually safe and does not create much of a current. Sponge filters will not trap or kill shrimp and my even benefit their overall health.Shrimp love to hang out on a sponge filter, feeding on debris collected and the microorganisms that live and grow inside the filter.

Shrimp seem to prefer having a substrate to walk around on as opposed to a bare bottomed aquarium. The best substrate for a shrimp tank would be a thin layer of fine sand. I have used a variety of commercially available substrates for planted aquaria and mixed my own with positive results. I have had success keeping and breeding shrimp using substrates that have buffered Ph to 7.2 or 7.4 and which have also increased calcium and hardness. The added calcium is good for shell development. I have experienced population explosions in aquariums with a Ph above 7, even with high grade Crystal Red shrimp. Last year I raised hunddreds of Crystal Reds in an aquarium with a Ph of 7.6. Conversely, most shrimp do not do well in higher Ph water that is around 8 or above.

I have tried keeping shrimp in water that was a lower Ph around 6.5 and low hardness with mixed results. Many shrimp keepers advise letting a layer of mulm accumulate on the substrate for the shrimp to sift through or placing Oak leaves into the shrimp aquarium. I have never practiced either of those techniques and have had no adverse results. I have not let mulm accumulate or let leaves decompose because I do not feel a high degree of decomposing waste is good for the water quality or overall shrimp health.

When aquascaping a shrimp tank provide large rocks or driftwood for the shrimp to explore. The surfaces of such decorations serve as sites for algae growth upon which the shrimp will feed. Most plants work well in a shrimp aquarium. One caution should be observed when adding plant life from commercial growers. Plants grown by commercial growers may have been treated with a substance possibly copper to kill snails; if a substance will kill snails it will definitely be toxic to shrimp. Soak and rinse new plants thoroughly before adding them to an aquarium containing shrimp.

When adding shrimp to an established planted aquarium or any aquarium, the shrimp should be drip acclimated to help them adjust themselves to the aquarium’s water parameters. Shrimp can be housed safely in aquariums that contain CO2 reactors. If the reactor fails the shrimp may be among the first residents in the tank to perish. I have used Seachem plant fertilizers without suffering any shrimp loss. As with adding any substance to a shrimp aquarium; dose fertilizers in trace amounts over a few days instead of one drastic dose.

When designing an aquarium specifically for shrimp try to plant it, so it can be easily cleaned and maintained. My favorite plant to use in a shrimp aquarium is Java mossVesiculariadubyana. Java moss is the only non-floating plant that I use in shrimp aquariums in most cases. I place a huge portion of java moss in the center of the aquarium to create a mountain like effect. I favor java moss because it is dense and can be easily moved when catching shrimp or cleaning the aquarium. The shrimp fully explore the moss and comb through the moss to make it look very nice.

Other plants that work well in shrimp aquariums are swords, Java fern Microsorumpteropus and various Valisneria species. Floating plants are a favorite place for shrimp to hangout upside down. Floating plant species such as Duckweed and FrogbitLimnobium sp. are fixtures in my shrimp aquariums because they provide a living filter.

As I have mentioned previously it is not a good idea to house fish and shrimp together. This does not mean that shrimp cannot have other types of tank mates. When housed together shrimp and snails have a great relationship. Snails likely produce microorganisms upon which baby shrimp feed. Substrate burrowing snails such as Malaysian Trumpet snails or Tarebiagranifera snails aerate the gravel and eat any food not consumed by the shrimp.

Algae eating shrimp can also be housed successfully with larger filter feeding shrimp such as Singapore Wood Shrimp (Atyopsismoluccensis) or the African Atyagabonensis. These larger peaceful shrimp have fans rather than claws and will not harm the smaller algae eating shrimp. I would not recommend housing algae eating shrimp with Macrobrachium sp. or any of the long armed shrimp varieties or dwarf crayfish. Both long armed shrimp and crayfish are predatory and will likely prey upon the smaller shrimp.

Different species of algae eating shrimp can be housed together safely. Care should be taken that both species are getting enough food because different species can become rivals and a more aggressive species might out compete a more submissive species for resources. Closely related species should not be housed together because they may interbreed. All members of the Caridinaserrata/cantonensis complex will freely interbreed with one another this includes Crystal Red shrimpCaridinacantonensis sp. Crystal Red, Bee shrimpCaridinacantonensis sp. Bee, Tiger shrimpCaridinacantonensis sp. tiger, and Bumble Bee shrimpCaridinacantonensis sp. Bumble Bee. Several Neocaridina species will also interbreed with each other Cherry shrimpNeocaridinaheterpoda var. red, yellow shrimpNeocaridinaheterpoda var. yellow, and snowball shrimpNeocaridina cf. zhangjiajiensis “white” will all interbreed. Neocaridina and Caridina species can be housed together without the threat of inbreeding.

Usually whenNeocaridina species interbreed the first generation offspring are dull brown or gray in coloration. I have seen some interesting Caridinacantonensis/serrata hybrids with wild striped patterns. Hybridizing may produce new shrimp varieties but is more likely to produce shrimp that look less attractive than their parents. Many of the brightly colored favorites such as snowball shrimp, crystal red shrimp, and cherry shrimp were created by the selective breeding of shrimp that exhibited a color variant rather than hybridizing species. In aquarium conditions shrimp produce offspring that exhibit many incredible color variations the possibility of new brightly colored shrimp morphs seem very likely in the years to come.

The water quality of a shrimp tank is very important especially when keeping delicate species such as Crystal Red shrimp. When keeping shrimp in a very small tank the water quality can deteorate rather quickly. That is why it is a good idea to keep shrimp in aquariums that are at least ten gallons. A shrimp aquarium should be cycled for a period of time just like any other freshwater aquarium.

I do a 25% water change and gravel vacuuming every 10 days on my shrimp aquariums. I add aged decholorinated tap water slowly into the aquarium over the span of twenty minutes. To limit the possibly of shock, I try to have the water that I am adding, around the same temperature as the water in the tank. Dumping water rapidly into the tank can stress shrimp and potentially shock and kill them. When shrimp stop eating they are likely reacting to poor water quality and it might be time for a water change. When shrimp are discolored or look cloudy they are sick and water quality should be checked. At this point little is known about shrimp disease so excellent care is the best prevention of illness.

After completing a water change I like to add about ¼ teaspoon of Instant Ocean marine salt per three gallons of new water being added to the aquarium. The salt will not harm plants in such a low dose and provides iodine, which is beneficial to the shrimp when they are molting. Liquid iodine can be dosed into the aquarium but if overdosed iodine can be lethal to shrimp. Shrimp molt when they are growing or some type of change/stress has occurred.

A day or two after a water change, the sheds which shrimp slough off when they molt are visible in the aquarium. Occasionally shrimp can be seen shaking themselves out of their sheds. The sheds look like clear or white shrimp lying on the bottom of the tank or on plants. Sometimes sheds are mistaken for dead shrimp. The sheds can be left in the tank for the shrimp to feed on. The sheds provide the shrimp with calcium and vitamins that have been depleted by molting. Dead shrimp are easily identified in the aquarium because they turn a bright salmon color and resemble a cooked shrimp.

Copper can be lethal to any invertebrate and is found in a variety of items that can find their way into a shrimp aquarium. Often, copper can be found in water that has sat in pipes for a prolonged period of time. To avoid water with excess copper in it, run the faucet for a minute to flush through any stale water, which may contain copper before using the water to fill the aquarium. Copper and copper sulfate are found in a variety of commercially prepared fish foods. Avoid using fish foods, which contain copper or copper sulfate because the amounts found in these foods could prove toxic. As mentioned previously, copper and pesticides can also be found on commercially grown aquatic plants. Plants from commercial sources should be rinsed and soaked before they are added to a shrimp aquarium.

Shrimp are browsers and feed constantly. To maximize the effect of the supplemental feedings, feed shrimp lightly several times per day as opposed to one heavy feeding. Feed shrimp an amount of food that will be consumed within one hour so leftover food does not pollute the aquarium. I like to use high quality pelleted foods. Sera manufactures a marine fish food that contains iodine which makes an excellent shrimp food. Variety is key when feeding algae eating shrimp. Shrimp can have most any type of pellet, wafer, or flake that does not contain copper. Feeding foods designed for vegetarian fish work very well for shrimp.

There are several types of Crystal Red shrimp foods available, which are manufactured in Japan. These foods enhance color and boost the immune systems of the delicate Crystal Red shrimp. The ingredients of these special Crystal Red foods are not listed so one could only speculate as to what produces the positive health and greedy reaction shrimp show when the food is dropped in the aquarium.

Shrimp love to eat algae if you have algae covered rocks or plants in other aquariums “rotate” them into the shrimp tank to be cleaned. Amano shrimp will eat most types of algae even beard algae if they are hungry enough. Shrimp love cyanobacteria, if you have some growing on lids or in other tanks drop some into the shrimp aquarium, they will relish the treat.

As treats dried seaweed and fresh zucchini can be offered to the shrimp with any uneaten portions being removed within several hours. I also feed shrimp frozen bloodworms and brine shrimp several times per week. The shrimp seem to prefer bloodworms. Live daphnia can be offered as a food as well. Often daphnia or small worms will grow in the aquarium which shrimp can be observed catching and feeding upon. These other invertebrates should not been viewed as pests but rather a sign of a healthy aquarium.

As mentioned earlier shrimp reproduce sexually, often when observing a colony of shrimp; males can be seen mounting females and mating with them. The male shrimp use specialized swimmerets to transfer sperm to females (Werner, 2003). The fertilized eggs are then held and rolled in the swimmerets located on the female shrimp’s abdomen.

Some species of fresh water shrimp use a primitive method of reproduction found in marine shrimp. In this mode of reproduction, females produce hundreds to often thousands of tiny eggs. After a period of incubation the larvae are released. The free swimming or floating larvae develop in salt water and undergo several larval stages before they take on a body similar to an adult shrimp (Werner, 2003). This type of reproduction is found in Marine shrimp and several species of freshwater shrimp including Amano shrimp Caridina japonica and Red nosed shrimp Caridinagracilirostris .

Most of the freshwater species of shrimp practice a more modern mode of reproduction (Werner, 2003). These species produce fewer eggs and carry them around for 21- 28 days. These species hatch into not larvae but well developed young shrimp that have already gone through all the larval stages in the egg. When released the young shrimp are miniature versions of their parents and eat the same type of food so they are easier to raise than free-swimming larval shrimp. Species such as Cherry shrimp and Crystal Red shrimp employ this modern mode of reproduction.

There are some species, which practice an intermediate or semi primative mode of reproduction (Werner, 2003). The young of these species are larvae when they hatch but assume a traditional shrimp body in a few days (Werner, 2003). Some of these species may require salt, or brackish water, while some species develop in freshwater (Ucozler, 2008). The larvae of species, which reproduce in this method require micro foods during their larval stage, which makes them somewhat harder to keep alive in the aquarium than species that release fully formed young.

If you have never kept shrimp before, I would recommend starting out with Cherry shrimp. Amano shrimp are very hardy but they aren’t as much fun because they are difficult to breed. Cherry shrimp are remarkably hardy, tolerating a variety of aquarium conditions. They are also among the most prolific of shrimp, once you get them established in an aquarium; you will likely have more Cherry shrimp than you know what to do with. Their bright red coloration and yellow eggs make them very attractive. Young cherry shrimp exhibit some red coloration so the tank will appear bright and alive. Cherry shrimp were the first algae eating shrimp that I kept and bred successfully and they are still one of my favorite types of shrimp, even after owning thousands of them.

That is one of the coolest aspects of shrimp keeping, in my opinion, being able to own thousands of something. Never, when I obtained my first six cherry shrimp did I think that I would own over five hundred of them in a few months. Once most shrimp start breeding, their numbers increase drastically and you run the risk of overpopulating an aquarium. Since algae eating shrimp do not cannibalize their young a separate tank for shrimplets is not necessary. In a well-cycled, well filtered, and heavily planted aquarium I would recommend not keeping more than five shrimp per gallon.

Selling shrimp can be extremely profitable because they grow and reproduce at a very rapid rate. When packaging shrimp for sale they can be packaged in a bag designed for transporting fish. All bagging procedures are the same as bagging fish, except for one thing: give the shrimp something to hold onto in the bag. Shrimp do not swim like fish; they need to be given something to hold onto when they are being shipped. If shrimp are not given material to hang onto they can injure each other by trying to cling to one another. Shrimp can also develop something like vertigo if they get very shaken up during travel. Provide shrimp with a bit of plant, rubber bands, or floss in the bag so they can have something to ride on while they are being shipped.

Shrimp keeping is difficult by no means. There are a lot of new rules to learn, an experienced aquarist or even a beginner should have tremendous success if they read a great deal and educate themselves prior to purchasing shrimp. Shrimp keeping has been popular in Germany and Japan since the 1990’s so much information is available from those countries; unfortunately much of it is not available in English. The following resources are very good for gaining quality information and staying current on all of the developments in the shrimp hobby.

www.shrimpnow.com European website with lots of great information.

www.crusta10.de Cutting edge information and awesome photos.

www.Planetinverts.com Great online invert community.

www.petshrimp.com The granddaddy of American invert websites great information.

Shrimp keeping continues to develop and has yet to crest and reach a zenith. Recently, many new exciting species have been discovered in the Sulawesi Lake Region of Indonesia. When I first saw the photos of these newly discovered, amazingly colored species such as Caridian cf. spongicola, I was speechless. I think the extreme excitement that I felt was similar to what cichlid keepers felt back in the 1970’s when a new cichlid was discovered in Lake Malawi or Lake Tanganyika. The Sulawesi discovery was extremely exciting because it consisted of more than ten new species. I have the feeling that discoveries like this will be common for years to come because shrimp are so tiny and new species could be lurking anywhere ranging from a lake to a tiny swamp. With more aquarists searching for new species, expeditions will traverse the globe attempting to satisfy the demand. Invert keepers are witnessing aquarium history being made and helping to write it themselves, rather than just reading about it in books written in the 1970’s.

I would like to close by thanking some folks who have made this article and my invert keeping experience possible: my family, Ed Pecord, JerineBlissett, Lee Finley, Mustafa Ucozler, David and Linda Giza, & Ned and Dan Bowers. Thanks to anyone who read this article, I hope you learned something and I hope that it becomes out dated rather quickly (that means more new developments).

Bibliography

Ucozler, Mustafa. www.petshrimp.com, (2008).

Werner, Uwe. Aqualog Special: Shrimps, crayfishes, and crabs in the freshwater aquarium 2^nd Edition. Verlag. Rodgau, Germany. (2003).